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ReBloom - Probablistic Datatypes Module for Redis

This module provides two datatypes, a Scalable Bloom Filter and a Cuckoo Filter. These datatypes are used to determine (with a given degree of certainty) whether an item is present (or absent) from a collection.

Quick Start Guide

  1. Launch ReBloom with Docker
  2. Use Rebloom with redis-cli

Note: You can also build and load the module yourself.

You can find a command reference in Bloom and Cuckoo Commands

Launch ReBloom with Docker

docker run -p 6379:6379 --name redis-rebloom redislabs/rebloom:latest

Use ReBloom with redis-cli

docker exec -it redis-rebloom bash

# redis-cli

Start a new bloom filter by adding a new item

#> BF.ADD newFilter foo
(integer) 1

Checking if an item exists in the filter

#> BF.EXISTS newFilter foo
(integer) 1

Building and Loading ReBloom

In order to use this module, build it using make and load it into Redis.


Invoking redis with the module loaded

$ redis-server --loadmodule /path/to/

You can find a command reference in and


In order to use this module, build it using make and load it into Redis.

Module Options

You can adjust the default error ratio and the initial filter size (for bloom filters) using the ERROR_RATE and INITIAL_SIZE options respectively when loading the module, e.g.

$ redis-server --loadmodule /path/to/ INITIAL_SIZE 400 ERROR_RATE 0.004

The default error rate is 0.01 and the default initial capacity is 100.

Bloom vs. Cuckoo

Bloom Filters typically exhibit better performance and scalability when inserting items (so if you're often adding items to your dataset then Bloom may be ideal), whereas Cuckoo Filters are quicker on check operations and also allow deletions.